Visual cognitive disturbance during spike-wave discharges.
Cognitive functions of patients showing slow spike-wave discharge in EEG without obvious absence seizures were investigated using tachistoscopic stimuli triggered by spike-waves. Response times obtained during spike-waves and during non-spike-waves were compared for three tests (tapping, simple reaction, and morphological discrimination). We present one case of Lennox-Gastaut syndrome in which the test results could be statistically confirmed. The tapping test was interrupted by the occurrence of spike-waves. Response times during spike-waves were more delayed than during non-spike-waves in both the simple reaction tests and morphological discrimination tests. The differences in response times measured during spike-waves and during non-spike-waves were significantly greater in the morphological discrimination test than in the simple reaction test. The positive correlation between the length of spike-waves and response time in the discrimination test was significantly more pronounced than in the reaction test. These results were also confirmed in two other patients with Lennox-Gastaut syndrome. We conclude that spike-wave discharges may impair cognitive processing more intrinsically than motor functions.
Sengoku
A
A
Kansai Regional Epilepsy Center, Utano National Hospital, Kyoto, Japan.
Kanazawa
O
O
Kawai
I
I
Yamaguchi
T
T
D000293:Adolescent; D003071:Cognition; D004192:Discrimination, Psychological; D004569:Electroencephalography; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011930:Reaction Time; D012640:Seizures / Q000503:physiopathology*; D014796:Visual Perception